Work-cutting mechanism for sewing machines



June 1950 H. c. FAULKNER WORK-CUTTING MECHANISM FOR SEWING MACHINES 4 Sheets-Sheet l I N VEN TOR.

Harold C: Fzwlbn 91 BY ATLORNEY Filed Nov. 14, 1947 WITNESS MQW June 20, 1950 FAULKNER' 2,512,227

WORK-CUTTING MECHANISM FOR SEWING MACHINES ,Filed Nov. 14, 1947 4 Sheets-Sheet 2 INVENTOR- Jfizrald a F5! 10 [kn er ATTORNEY June 20, 1950 H. c. FAULKNER WORK-CUTTING MECHANISM FOR SEWING MACHINES 4 Shee'ts-Sheet 3 Filed Nov. 14, 1947 INVENTOR. flare [d aiualfiner ATTORNEY WITNESS June 20, 1950 H. c. FAULKN ER WORK-CUTTING MECHANISM FOR SEWING MACHINES.

4 Sheets-Sheet 4 Filed Nov. 14, 1947 INVENTORQ afar-0Z0? 6f ATTORNE Y 3 eflfect the shifting of the work-clamp, the lower work-plates I8 thereof are carried on a supporting slide 22 provided, at opposite sides and near the front thereof, with a pair of depending lugs 23. Each of the lugs 23 has fixed therein a. pin 24 on which is pivoted the upper end of a short rocker 25 pivoted at its lower end on a pin 26 fixed in the machine-bed I0. At its rear end the supporting slide 22 has secured to it a crossplate 21 formed substantially at its mid-point with spaced lugs 28 (Fig. -2) between which is pivoted the upper end of a rocker 29 fulcrumed at its lower end, as at 30, on the bed In. The rockers 25 and 29 are substantially the same length and are preferably disposed so that during the initial movement of the supporting slide 22 the same rises substantially vertically to clear the needle-throat member 20, after which the supporting slide, together with the work-clamp, move rearwardly into work-cutting position.

The mechanism for shifting the work clamp into and out of work-cutting position is best shown in Fig. 6. Secured to the rocker 29 is one end of a link 3| connected at its other end to one limb of a bell-crank lever 32 pivoted at 33 on the machine-bed H). The other limb of the bell-crank lever 32 is connected by a forwardly extending link 34 to the front end of an actuating link 35 slotted, as at 36, to receive a slide-block 31 loosely mounted on a cutter-shaft 38 and fitted with a follower-roller 39 adapted to track the cam-groove 4B in the cutter-advancing and -retracting cam 4| mounted on the cuttor-shaft 38. The pivotal connection between the link 34 and the actuating link 35 (Fig. 9) comprises a shouldered sleeve 42 through the bore of which projects a bolt 43 having a T- shaped head 44 disposed in a correspondingly shaped open-ended slot 45,formed in the rearwardly extending projection 46 of a fulcrumblock-41 slidable in suitable ways in the bed and supporting a pair of cutter-levers later to be described. The .bolt 43 and the slot 45 provide means for elfecting adjustment between the cutting elements and the work-clamp, whereby the cut eye can beaccurately located in the .center of the eyelet. To assist in securely fastening the bolt 43 tothe fulcrum-block projection 46 there is provided a second clamping nut 48'. It will be understood that the cutter-shaft 38, which is stationary during the sewing, will make one complete revolution before or after the stitching cycle is completed and that during this revolution of the shaft the cam 4|, through the actuatin link 35, shifts the, fulcrum-block 41 toward the left (Fig. 6) carrying the cutting elements into work-cutting position. Simultaneously with the movement of the fulcrum-block 41, the cam 4|, through the linkage 3| to 34, effects a shifting of the supporting slide 22 on its supporting rockers 25 and 29, causing, first, a raising of the supporting slide to clear the needle-throat member 20 ,and, second, a movement of the supporting slide and work-clamp to the right (Fig. 6). This movement of the workclamp and cutting elements towards each other into cutting position, shown in Figs. 3 and 4, minimizes the time required for the eyelet cutting cycle and also eliminates the usual tipping I needle-throat member used in the machine disclosed in the U. S. patent of E. B. Allen, No. 1,048,786, issued December 31, 1912. In the present machine, the preferred proportions of the various links and levers are such that the fultwice that of the work-clamp. After the work cutting operation is completed the work-clamp is returned to the stitchin position and the cutting elements to their retracted or inoperative position.

The work-cutting mechanism now to be described comprises a lower cutter-lever 48 fulcrumed on the pivot-pin 49 in the fulcrum-block 41. Straddling the lower cutter-lever 48 (Fig. 4) at a point rearwardly of the fulcrum-block 41 is the depending bifurcated projection 59 of an arched upper cutter-lever 5| pivoted to said lower cutter-lever 48, on the pivot-pin 52. The rear ends of the upper and lower cutter-levers 5| and 48 are cooperatively related with the respective cutter-lever closing cams 53 and 54 mounted on the cutter-shaft 38, the two cutter-levers 48 and 5| being yieldingly maintained in contact with these cams by a coil spring 5| which acts between said cutter-levers.

As will be seen in Figs. 7 and 8, the lower cutter-lever 48 has adjustably mounted on its front end a die 55 having a shank 53 apertured as at 51 to receive a clamping screw 58 threaded into the lower cutter-lever 48. Formed in the bottom face of the die-shank 56 is a longitudinal groove 59 into which projects a guide-tongue 69 provided on the top face of an adjustment block 8| which on its bottom face is formed with a transverse guidetongue 62 fitted into a groove 63 cut into the lower cutter-lever 48. The aperture 51, is sufliciently enlarged to permit adjustment of the die 55 when the clamping screw 53 is loosened, the tongues 60 and 62 and grooves 59 and 63 confining the adjustment of the die along predetermined lines.

Cooperating with the die 55 in cutting the work is a punch 64 which is adapted to enter a hole 65 formed in the die 55, the hole 65 preferably flaring outwardly slightly toward the .bottom of the die so that the punchings or cut-outs will not tend to follow the punch when it iswithdrawn from the die but will be retained and forced onward by the succeeding cut-outs. The punch 64 is mounted in a carrier or slide-bar 66 endwise slidably in a vertically bore head-piece 61 secured for limited sidewise adjustment by a screw 68 on the free end of the upper cutterlever 5|. The punch 64 is retained in the sliderod 65 by a set-screw 69, the body of which extends through a slot 18 in the head-piece B1 and prevents turning of the slide-rod 66 in the headpiece 61. The carrier 56 is reciprocated in the head-piece 81 by means of a punch-actuating lever ll fulcrumed intermediate its ends on .a pivot-stud 12 provided on the upper cutter-lever 5|. At its rear end the punch-actuating lever is engaged by a cam 13 which imparts the workcutting stroke to the punch 64. A coil-spring 14 maintains the rear end of the punch-actuating lever in contact with the cam 13. To effect a positive withdrawal ofthe punch 64 from the die 55 after the work-cutting operation is completed, the punch-actuating lever 1| is provided with a follower-roller 15 which is disposed to cooperate with a cam-groove 16 shaped to pivot the lever 1| about the stud 12 and raise the punch-carrier 63 in the head-piece 51.

To facilitate disposal of the cloth chips beyond the range of the stitching mechanism, I" have provided an inclined chute 11 which is substantially U-shape in cross-section and mounted on the turret 2| so that its upperend underlies the crum-block 41 moves a distance substantially '75 punch-hole 65 in the die 55. the lower and disserene ret 2 I i Operation the operation of themachine, theworkQW inserted beneath the upper clamp-feet. 19. of. the; world-clamp, after which the. machine is tripped into action by the operator depressing themsualetarting button-\which initiatesthe .singlerrevolutionof: the cutter-shaft 38. Theinitial movement of the cutter-shaft 38 closes .the work.- cla mprupon. the work, while, the cutter-levers 48 andwiill remain open anddn their. retractedposig tion removed from sewing position, .as.shojwn in Eig pl. Continued. movementeof the-cutter-shaft 38, then effects asimultaneous. shifting of the work-:clamp and the cutting. elements towards each other tocause them to meetat ag-iven 011th tine: position intermediate the stitching pgosition and the normaliretracted position. of. the. cutting elements. The means by which this simulta neouswshift is accomplishedhas been previously fill-1y described. During theforward movement of. the cutting mechanism from retracted position .to. cutting position, the cutter-leversAB and 5|, under the action .of the cutter-leverclosir'ig cams 53 and54, are caused relatively toapproacli each other, moving into a punch-and-die alined position, shown in Fig. 3. The twocutter-levers 48 and-5| remain in this position for the duration of the concentric portions of the two cams 53 and 54. To lock the cutterelevers 48 and 5| against. further movement towards each other, there is provided rearwardly of the pivotal connection 52 between the two cutter-levers a tielink 19 (Fig. 5) pivoted at its lower end to the IOWGI'lCl-lttBY-IGVGI' 48 and having its upper end slotted; as at Bil, through whichslot projects a limit-pin fll fastened on the upper cutter-lever Salt; Cooperating with the limitepin 8| in eliminating any accidental movement between the two cutter-levers 48 and 51 is a stop-screw 82 threaded into the top of the tie-link 19. It will be understood from the above that the two earns 53 and 54 operate to move the two cutter-levers 48 and 51 towards each other into punch-anddie alined position and that the tie-link l9 and the cams 53 and 54 cooperate to rigidly lock the two cutter-levers against any movement which might affect the alined position of the punch and die during the traversing of the concentric portions of the cams 53 and 54.

When the cutter-levers 48 and 5| are brought into punch-and-die alined'position, the punchoperating cam 13 engages the rear end of the punch-actuating lever ll (Fig. 3) causing it to turn about the pivot-stud 12 and force the punch 64 downwardly through the work and into the die 55, as shown in Fig. 4. The cloth-chip cut from the work by the punch 64 is forced into the punch-hole 65 which strips the cloth-chip from the punch when the latter is retracted. The punch 64 is forcibly withdrawn from the die 55 by the cam 16 contacting the roller on the rear end of the punch-actuating lever 7 I. It will be appreciated that the coil-spring 14 normally will function to separate the punch 64 from the die 55, but in the event the punch accidentally sticks in the die the cam 76 and roller 15 will forcibly withdraw the punch and prevent damage to the stitching mechanism during its subsequent operation. After the punch has been withdrawn from the die, the coil-spring 5| operates to open the two cutter-levers 48 and 5 I, this action occurfil ring during the"returm'oflthe:cuttingfmeclianisnir touts-inoperativepositionshowminliig. 1 .J I n I-t -wil'-l-= be. understoodvfroma the foregoing i that I" have invented a work".- cutting-:mechanismewhiclr is positivein its. action, and i will requirexlittlsy. upkeep:- After theinitial propersetting of the puncli-and: die is attained, resharpening of the punch" canlbei accomplished. without disturbing thissetting. Toresharpen the'punch it is::-neces.-,- sary merelyto. loosen the screw liar and: remove the punch 64 fromits carrier; 6.6. The shape-oh the-two cutting-levers and 51;. and the disposition-20f 'theipivot-pinsi 49*and 52. give considerable clearancea space under. theupper cutting-lever. 5.1,

w fbr'-theawork'..W and also'for certainofthemech..--

anismi of the. workeclamp. It1.w ill be understood thatdifierentsize :punches and dies may be-used in theemechanism. Also, when making small eyelets"; as. pointed: punch. may, be employed. in whichzacase the. material is pierced without-cuttingi a :slug therefrom and. the displaced. threads area-crowded; around the edge of: theeye; creating a reinforcement therefor.

Having 'thus set forth .the: nature :of the; invention', what I. claimzherein is:

1'. A workcutting mechanismafor a sewing ma.- chinehaving .abed; c0mprising,..a-i lower cutting,- elements a lower cutter-lever'carryin'g said lower cutting element and supported onaifulcrum-axis provided? on said machine bed, .an upper cuttingelement; an upper cutter-leverrcarryingg said-up.- pen cutting-element and pivotally. mounted. on said lower: cutter-lever on. an; axis spaced from th'eisupportingi fulcrumeaxis of said lower cutter? levem.and.-'cutter+lever actuating meansfor efe fectingi a relative:..movement between said upper andzlower cutterelevers;

2: A work cuttingzmechani'sm for a-sewingma; chine having a bed, comprising, a lower cutting;- eiementrailowerrcutterlever carryingssaidrlower cutting-element .andsupported' on a fulcrum-axis provided on said machmez-bed j. an upper cuttings lever pivotally mounted on said lower cutterlever on an axis spaced from the supporting fulcrum-axis of said lower cutter-lever, an upper cutter-element mounted on and movable relative to said upper cutter-lever, means for effecting relative movement between said upper and lower cutter-levers, and lever-means for moving said upper cutting-element relative to said upper cutter-lever.

3. A work-cutting mechanism for a sewing machine having a bed and an actuating shaft, comprising, a die, a die-carrying lever supported on a fulcrum-axis provided on said machine bed, a punch-carrying lever pivotally mounted on said die-carrying lever on an axis spaced from the supporting fulcrum-axis of said die-carrying lever, a punch mounted on and movable relative to said punch-carrying lever, means for moving said die-carrying lever and said punch-carrying lever into a punch-and-die alined position, and means for moving said punch relative to said punch-carrying lever and into said die, said means including a pivotally mounted lever connected on one end directly to said punch and at its other end operatively associated with said actuating shaft.

4. A work-cutting mechanism for sewing machines having a bed and an actuating shaft, comprising, a die, a die-carrying lever supported on a fulcrum-axis provided on said machine bed, an arched punch-carrying lever having a depending portion mounted on said die-carrying lever for pivotal movement on an axis spaced rearwardly froin the supporting fulcrum-axis of said die:-.--

carrying lever, a punch mounted on and movablev relative to said punch-carrying lever, means for moving said die-carrying lever and said punchcarrying' lever into a punch-.and-die alined position, and means for thereafter moving said punch relative to said punch-carrying lever and into said. die, said means including av pivotally mounted lever connected at one end directly to said punch and at its other end operatively associated with said actuating shaft.

5. A work-cutting mechanism for a sewing machine having a bed and an actuating shaft, comprising, a die, a die-carrying lever supported on a fulcrum-axis provided on said machine bed, a punch-carrying lever pivotally mounted on said die-carrying lever on an axis spaced from the supporting fulcrum-axis of said die-carrying lever, a punch mounted on and movable relative to said punch-carrying lever, means for moving said die-carrying lever and said punch-carrying lever into a punch-and-die alined position, means for locking said levers in said punch-anddie alined position, means for moving saidpunch relative to said punch-carrying lever and into said die, said last named means including a pivotally mounted lever connected on one end die rectly to said punch andat its other end opera atively associated with said actuating shaft.

6. A work-cutting mechanism for a sewing machine having a bed and an actuating shaft provided with a plurality of cams, comprising, a die, a die-carrying lever supported on a fulcrum-axis provided on said machine bed, a punch-carrying lever pivotally mounted on said die-carrying lever, a punch mounted on and movable relative to said punch-carrying lever, said die-carrying lever and said punch-carrying lever being operatively associated with at least one of said cams whereby said levers are moved into a punch-anddie alined position, a tie-link connected to each of said levers and cooperating with said. cams for locking said levers saidpunch-antl dle alined position, andmeans for moving said puncli'i relative to said punch-carrying lever afidiiitol said die. v

7. A work-cutting mechanism for a sewing machine having a bed and an actuating shaft provided with a cam, comprising, a die, a die-carry ing lever, a punch-carrying lever pivotally sup-' ported on said die-carrying lever, a head-piece secured'on said punch-carrying lever, a carrier-' member slidably mounted in said head-piece, a punch secured in said carrier-member, and a punch-actuating lever connected at one end directly to said carrier and at its other end adapted to be connected directly to said cam; 8. A sewing machine having stitch-forming devices, a work-clamp adapted to hold work in stitching position, a work-cutting device having cutting elements normally occupying an inoperative position remote from said stitching position; and mechanism for shifting the work-clamp and the work-cutting device substantially simultaneously to a cutting position between said stitching position and the inoperative position of said work-cutting device, said mechanism including a cam, anactuating link connected to said cam and to said work-cutting device, a bell-crank lever operatively associated with said actuating link, and a connection between said bell-crank lever and said work-clamp.

HAROLD C. FAULKNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Allen Sept. 30, 1930 

